Why do Muslim women cover their hair?

Praise be to Allah, the Lord of the Worlds; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.

Islam honours, dignifies and respects the woman, and protects her from all kinds of harms.  A woman in Islam is like a jewel.  A jewel is usually safely kept in a luxurious box in order to keep it from being distorted.  In order to protect and honour a Muslim woman Allah legislated Hijab (veil – a Muslim woman's dress), because this veil covers her beauty.  Nobody is allowed to take pleasure by looking at her except her husband whom Allah has permitted.

In this way a Muslim woman does not feel that she is humiliated, nor does she fear being considered as an object that can be sold or bought.  Besides, she covers herself from unwanted glances and from being used as an advertisement tool in magazines and newspapers.  These pictures usually incite men's desires.

On one hand, a Muslim woman who wears the Hijab feels that she is dignified and honoured in addition to her fulfilling the ordainment of her Lord. 

On the other hand, Allah Ordered her to cover her beauty in order to prevent affliction and mischief which is caused by women exposing their beauty.  This fact can only be denied by a stubborn person.

Allah knows best.